1. Field of the Invention
This invention concerns a wire stripper for automatically stripping the coating off the end of a coated wire in a required length. The invention further concerns a centering device for the wire stripper.
2. Discussion of the Prior Art
Various wire strippers have been made available which serve for stripping the coating off the end of a coated wire and exposing the core in a required length.
With such conventional wire strippers, in general, a coated wire is inserted into a machine and gripped at the end from both sides by grippers, and is nipped at the same time by cutters from both sides where its coating is to be cut. The cutters cut only the coating and strip the coating away from the wire end while being withdrawn.
Cutters and grippers of such conventional wire strippers are opened and closed by reciprocating motion of a cutter/gripper operating element by means of an pneumatic cylinder (or hydraulic cylinder) or through operation of cutter/gripper operating cams by means of an electric motor.
To mention some of the problems concerning conventional wire strippers, the pneumatic or hydraulic cylinder necessitates a compressor or a hydraulic unit, respectively, in addition to the wire stripper, which remarkably restricts the place where such wire stripper can be used in combination with such equipment. Furthermore, the compressor causes high exhaustion noise and may adversely affect the mechanism due to moisture contained in the air.
The variation using cams requires large decelerator and large components including a coupling because an electric motor has to be used separately for each motion, or motor rotation has to be transmitted to the cam only after substantial deceleration, which results in large and expensive wire strippers.
The present invention has the object of providing a remarkably small, quiet and inexpensive wire stripper without restrictions about location of use because gripping of wire and stripping of coating can be performed by means of a conventional reversible motor. A main spindle is supported on machine frame, being allowed to slide longitudinally, and is reversible in rotation by means of only one motor and is provided with a lead-screw shaft coupled with a nut block. The lead-screw shaft moves forward to the nut block by forward rotation of the main spindle to close the grippers and the cutters and at the same time to rotate the cutters. The nut block moves backward to retract the cutters after the main spindle has stopped to advance.
The invention further has the object of providing a wire centering device for the wire stripper.
The invention aims at providing an inexpensive compact wire stripper capable of automatically grasping a coated wire, cutting the coating with cutters, rotating the cutters and stripping the cut coating away by means of only one electric motor. This is accomplished in the present invention as follows: A wire stripper according to the invention is provided with a reversible main spindle which is supported on machine frame and allowed to slide crosswise so as to enable gripping operation of the grippers as well as nipping and cutting operation of the cutters. The main spindle is provided with lead-screwed shaft with which a nut block is coupled so that the lead-screwed shaft advances by forward rotation of the main spindle to close the grippers and the cutters as well as to rotate the cutters. The nut block is then moved backward by the lead screw of the lead-screwed shaft after the main spindle has stopped to advance and the cutters are then withdrawn to strip the cut coating away from the core.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, and specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.